A multicapillary electrophoresis device using a laser as the excitation light source and used for detecting fluorescence, typified by a DNA sequencer, has high reliability in producing analysis results; therefore, it is still widely used even now in the era when a base sequence analysis device with a markedly high throughput like a next-generation sequencer has permeated. Equipment used for the purpose of analyzing genes other than a DNA sequencer are required to have even higher separability and high sensitivity.
On the one hand, the equipment for processing many samples at high sensitivity and a high throughput needs a huge optical system and precise and expensive capillary cassettes. On the other hand, in the equipment for processing a comparatively small number of samples, there is no equipment with a detection optical system configured to be compact and have high sensitivity and a low capillary cost.
The capillary cassette used in a multicapillary electrophoresis device needs to be changed to a new one since the cassette is a consumable good whose characteristics unavoidably changed over time. When a capillary cassette is mounted to a multicapillary electrophoresis device, a relative alignment of the capillary center in a detection section and an optical system must be realized while maintaining convenience for a user.
As an electrophoresis device of a system in which a capillary cassette is exchanged, the following capillary electrophoresis device has been proposed: a capillary array is supported by a resin (plastic) frame, and a holding part of a sample injection end, a capillary bending part, a detection part, and an injection end holding part of a separation medium are fixed according to a predetermined procedure, respectively (see Patent Literature 1).
A multichannel cartridge easily replaced as a unified cartridge structure containing optical elements and a reagent reservoir in which the alignment has been carried out in advance has also been proposed as another system of a capillary cassette (see Patent Literature 2).